Cathodic protection for water tanks

ABSTRACT

D R A W I N G THE PRESENT INVENTION DISCLOSES A SUPPORT SYSTEM FOR CATHODIC PROTECTION APPARATUS USED IN LIQUID CONTAINING METAL TANKS WHEREIN SUBMERGED ANODES ARE ATTACHED TO BUOYANT SUBMERGED CONDITION BY FLEXIBLE ATTACHMENT TO A TOTALLY SUBMERGED CONDITION BY FLEXIBLE ATTACHMENT TO THE WALLS OF THE WATER TANK, THEREBY PREVENTING ICE ACCUMULATION ON AND DAMAGE TO THE ANODES.

Feb. 27, 1973 L. K. JACOBS ET AL CATHODIC PROTECTION FOR WATER TANKSFiled Sept. 18, 1969 FIG.3

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INVENTORS LLOYD K. JACOBS 8\ RICHARD N. HULL ATTORNEY United StatesPatent Oflice 3,718,554 CATHODIC PROTECTION FOR WATER TANKS Lloyd K.Jacobs, 430 Allen Drive, Vine Grove, Ky. 40175, and Richard N. Hull,Rte. 1, P.O. Box 145, Irvington, Ky. 40146 Filed Sept. 18, 1969, Ser.No. 858,989 Int. Cl. C23f 13/00 U.S. Cl. 204-147 4 Claims ABSTRACT OFTHE DISCLOSURE The present invention discloses a support system forcathodic protection apparatus used in liquid containing metal tankswherein submerged anodes are attached to buoyant submerged means, whichmeans is maintained in a totally submerged condition by flexibleattachment to the walls of the water tank, thereby preventing iceaccumulation on 'and damage to the anodes.

The invention described herein may be manufactured and used by or forthe Government for governmental purposes without the payment to us ofany royalty thereon.

BACKGROUND OF THE INVENTION The invention generally relates to structurefor support ing anodes inside liquid containing tanks to providecathodic protection for the tanks and to prevent the formation of ice onthe anodes.

SUMMARY OF THE INVENTION 1 The impressed current method of cathodicprotection for liquid containing metal tanks is well known in the art.In the absence of cathodic protection, metal tanks, particularly thosecontaining ionic solutions, establish localized electrolysis on theinterior of the tank causing corrosion on the tank wall.

By inserting anodes into the tank and sending direct current through theanodes a current flow is established from the anode, through the liquid,the tank wall, and to a ground, although the tank itself may serve as aground. This system prevents corrosion of the tank.

The anodes must be suspended in the liquid in some manner. The roof ofthe tank serves as a means for attaching the cable to which the anodesare connected. Since the liquid level in the tank is variable, the cableattached to the roof and several of the anodes connected to the cablemay be above the liquid level. In colder climates during the wintermonths these exposed parts have ice deposited on them which can resultin damage to the cable or the anodes due to the weight of iceaccumulation. Loss of anodes results in the breakdown of the cathodicprotection and requires yearly repair of the protection system.

It is, therefore, an object of the present invention to provide meansfor suspending anodes in a liquid containing tank such that the anodeswill not be susceptible to damage due to ice accumulation.

This object is achieved by securing by some flexible, non-metallic meanssuch as a rope, nylon cord or polyethylene cord, a buoyant submergedmeans to the lower walls of the tank, and attaching the anodes to thebuoyant submerged means.

The buoyant submerged means which may be of any material which willfloat in the liquid in question is maintained below liquid level by atie line from the means to the tank walls, preferably being attached insuch a manner that the means will be prevented from attaining lateralmovement which would cause the anodes to contact the tank walls.

3,718,554 Patented Feb. 27, 197? BRIEF DESCRIPTION OF THE DRAWINGS FIG.1 is an elevational view partly in section of the water tank and thebuoyant submerged means attached to the walls by tie lines;

FIG. 2 is an isometric view of the buoyant submerged megns showing anodeattachments on one side member; an

FIG. 3 is a sectional view taken on line 33 of FIG. 2 showing the anodesattached to a side member of the buoyant submerged means.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows tank 1 which may beof any configuration or size containing liquid to level 11. Within thetank, but below liquid level is buoyant submerged means 2. Buoyantsubmerged means 2 is kept from floating to the surface by tie lines 3which are attached at one end to the tanks lower surface by any suitableattaching means and at the other end to the buoyant submerged means 2,thereby restraining the buoyant submerged means 2.

FIG. 2 shows buoyant submerged means 2 in an isometric view as beingsquare or rectangular in shape. The shape of buoyant submerged means 2is not, of course, limited to this configuration, but may take on anydesired configuration so long as it remains buoyant. Further, buoyantsubmerged means 2 may be of any material which will float in the liquidcontained by the tank.

In the embodiment of FIG. 2 tie lines 3 attach to the four corners ofbuoyant submerged means 2. This type of attachment prevents lateralmovement of buoyant submerged means 2, thereby preventing damage to theanodes from contact with the tank wall. Any sort of attachment whichwill both secure the buoyant submerged means 2 to the tank and preventlateral movement of buoyant submerged means 2 is within the scope of theinvention.

As shown in FIG. 2, buoyant submerged means 2 is made from wood and itsbuoyancy is increased by the addition of flotation cells 12 which areattached at the interior corners of buoyant submerged means 2 by block13 and securing lines 5. The flotation cells may be of any materialwhich will increase the buoyancy of buoyant submerged means 2 and may bestyrofoam or the like.

As shown in FIG. 1, direct current passes through electrical line 4 fromoutside the tank. Electrical line 4 is insulated and secured to the sideof tank 1 until electrical line 4 reaches the point at which one of tielines 3 is attached to the tank 1. At this point electrical line 4 islooped to permit slack in electrical line 4 and is attached along thelength of tie line 3 to submerged means 2. The anodes 6, which may be ofany standard design, are connected serially in line with electrical line4 and are attached to both the top and bottom of side members 14 ofbuoyant submerged means 2.

Anodes 6 are attached to side members 14 as shown inin FIG. 3 by meansof block 7 and tie line 8. Block 7 has first longitudinal groove 10which is shaped to conform to the shape of the anode 6. Andoe 6 rests ingroove 10 thereby providing added stability. Block 7 has a second groove9 which is shaped to conform to the configuration of the top and bottomsides of side member 14. Side member 14 is inserted into groove 9 suchthat the sides of block 7 partially enclose side member 14.

After block 7 has been placed on side member 14 and anode 6 has beenlaid into groove 10, tie line 8 is inserted through hole 15 in sidemember 14, is wrapped around block 7 and anode 6, and is tried to secureanode 6 to side member 14. There are a plurality of anodes attached toboth the top and bottom of side members 14 in like fashion. Block 7 isemployed to prevent damage to anode 6 and should be a substance such aspolystyrene or the like which will not provide a hard anode-blockinterface.

It is to be understood that any suitable anode attaching technique iswithin the purview of this invention, the configuration of the buoyantsubmerged means 2 determining how the anodes should be attached.

We claim:

1. A method of protecting a metallic liquid containing tank againstcorrosion comprising the following steps:

(a) attaching anode means and associated electrical conductors to anon-conducting buoyant support means;

(b) totally submerging said buoyant support means and attached anodemeans in the contained liquid 1 by anchoring means directlycommunicating with a lower portion of said tank; and

(c) impressing direct current to said anode means through saidassociated electrical conductors which emanate from a power source.

2. A method of protecting a metallic liquid containing tank againstcorrosion according to claim 1 wherein said anchoring means areflexible.

3. A method of protecting a metallic liquid containing tank againstcorrosion according to claim 1 wherein said anode means are in directcontact with said buoyant support means.

4. A method of protecting a metallic liquid containing tank againstcorrosion according to claim 1 wherein said associated electricalconductors emanate from a power source located outside said tank.

References Cited 20 TA-HSUNG TUNG, Primary Examiner US. Cl. X.R.204--196

